Getting a flu vaccine still remains the best protection for you and your family against the flu. Oregano oil, also known as P73, has been shown in small lab studies to have antiviral, antibacterial and anti-inflammatory properties.
In a 2010 study published in the medical journal Scientia Pharmaceutica, olive leaf capsules were described as having antiviral properties to the respiratory viruses R.S.V. and parainfluenza, although it has not yet been proven to be effective against influenza.
Black elderberry extract, which is available in tea, liquid and capsule form, is thought to work by blocking the flu proteins called hemagglutinin, according to Ashton.